Answer:
6370 J
Explanation:
By the law of energy conservation, the work done by the student would be the change in potential enegy from 1st floor to 3rd floor, or a change of 13 m

where m = 50kg is the mass of the student, g = 9.8 m/s2 is the gravitational constant and h = 13 m is the height difference

fraction equation is<span>
F =µR
F=friction,µ=coefficient , R=reaction = mg
use same equation for b part, but the reaction is no longer mg because the plain is now inclined. Draw a forces diagram and you will see that the reaction force can be calculated from the weight of the object and inclination of the plain using trigonometry.</span>
The body moves at a velocity of 1.62m/s after the bullet emerges.
<h3>Given:</h3>
Mass of bullet,
= 22g
= 0.022 kg
Mass of the block,
= 1.9 kg
Velocity of bullet ,
= 265 m/s

According to the law of collision which states that the momentum of the body before the collision is equal to the momentum of the body after the collision.
After penetration;


The formula for calculating the collision of a body is expressed as:
p = mv
m is the mass of the body
v is the velocity of the body
∴ Momentum before = Momentum after
Substitute the given parameters into the formula as shown:

Therefore, It moves with a velocity of 1.62 m/s.
Learn more about momentum here:
brainly.com/question/25121535
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